An inkjet printing apparatus forms an image on a medium by discharging ink droplets from nozzles according to an image signal. One type of the ink jet printing apparatus is a piezoelectric element type.
An ink jet printing apparatus of the piezoelectric element type has an ink jet head that includes a nozzle plate. The nozzle plate includes a nozzle and an actuator having a piezoelectric film and metal electrode films formed on both surfaces of the piezoelectric film. Ink is discharged through the nozzle by applying a voltage to the actuator.
Quality of the image formed depends on an accuracy of ink discharging positions, and the accuracy depends on the shape of the nozzle. Thus, when the shape of the nozzle is not uniform, the accuracy of the ink discharging positions may decrease and, as a result, the quality of the image may become worse.